The present invention relates to an information processor, a control method, a program and a recording medium. More particularly, the present invention relates to an information processor in which an energy saving function is controlled, and a control method, a program and a recording medium for this control.
In recent years, an energy saving technique for extending the battery drive time of portable information terminals or the like has attracted attention. For example, a technique for changing power consumption according to the amount of computation processing has been used. An example of this is a paper written by Compact Computer Corporation and other four companies entitled, “Advanced Configuration and Power Interface Specification Revision 2.0a”, Mar. 31, 2002.
In portable information terminals using the above-described technique, there is a possibility of occurrence of noise (acoustic noise) due to periodic change in power consumption of a processor. For example, a capacitor used for stabilizing power supplied to a processor repeats charge and discharge each time power consumption is periodically changed. By this charge and discharge, the capacitor expands and contracts to cause a mount board to warp periodically and to vibrate by warping. If the number of contraction and extraction cycles is in an audible frequency band, the portable information terminal generates noise harsh to the user's ear.
Therefore, an object of the present invention is to provide an information processor, a control method, a program and a recording medium capable of solving the above-described problem. This object can be attained by a combination of features described in the independent claims in the appended claims. In the dependent claims, further advantageous examples of the present invention are specified.